Aircraft passenger seat

ABSTRACT

A drive  35, 37  reversible to two active states for optional generation of a force of displacement effecting retraction or extension of a foot rest configuration  11  is provided in an aircraft seat having seat components such as backrest, seat element  1 , and leg rest  9  which is coupled to the front edge area  3  of such seat element and which may be pivoted between a lowered non-use position and raised use position, and having a foot rest configuration  11  mounted so as to be movable longitudinally on the leg rest  9  between a retracted position and an extended position to form and extension of the leg rest  9  and is coupled to a drive  35, 37  which may be switched between an inactive state of rest and an active state generating a force for displacement of the foot rest configuration  11.

The invention relates to an aircraft passenger seat having seat components such as backrest, seat element, and a leg rest which is coupled to the front edge area of the seat element and which may be pivoted between a lowered non-use position and raised use positions, and having a foot rest configuration which is movable longitudinally on the leg rest between a retracted position and an extended position to form an extension of the leg rest and which is connected to a drive which may be switched between an inactive rest state and an active state generating a displacement force applied to the foot rest configuration.

Aircraft passenger seats of this type have already been disclosed; see U.S. Pat. No. 5,352,020. The possibility of increasing the total length of the leg rest plus foot rest configuration makes a sufficiently long application surface available to the seat occupant, although only the short structural length reaching from the seat element to the cabin floor is available in the non-use position for leg rest and foot support configuration.

A spring force accumulator, which may be blocked and unblocked by means of a control valve which the seat occupant may operate, is provided for application of the force of displacement to the foot rest configuration in the aircraft passenger seat disclosed. When the spring force accumulator is unblocked, a displacement force acting on the foot rest configuration retracts the latter into the leg rest. In order to extend the foot rest configuration when in the raised position, the seat occupant must use his leg muscles to extend the foot rest against the retraction force generated by the spring force accumulator into the use position and then block the spring force accumulator by actuating the control valve.

In that the value assigned to the displacement force generated by the spring force accumulator must be high enough to ensure reliable retraction, the seat occupant suffers the disadvantage of strenuous operation, since the displacement force must be overcome in order to use the foot rest configuration.

On the basis of this state of the art, the object of the invention is creation of an aircraft passenger seat of the type under consideration, one which is distinguished by especially easy operation.

It is claimed for the invention that this object is attained with an aircraft passenger seat of the type referred to in the foregoing in that a reversible drive which may be switched to two states of operation is provided for optional generation of a displacement force effecting retraction or extension of the foot rest configuration.

While in the case of the disclosed aircraft passenger seat only retraction of the foot rest configuration is effected by the drive, that is, only a control measure is required for the retraction, the invention makes it possible to move the foot rest configuration into the use position desired by motive means as well, that is, by a simple control measure not requiring expenditure of force, so that a maximal degree of convenience of operation is achieved.

In preferred exemplary embodiments the drive has an electric gear motor permitting reversal of the direction of rotation. Consequently, only operation of an electric switch configuration is required for control, so that the greatest reliability and convenience of operation are ensured.

In exemplary embodiments in which the geared motor has a pinion on the output side, the configuration devised may be such that the pinion engages two parallel racks of which one end is hinge-connected to the structure of the leg rest and the other is hinge-connected to this movable foot rest configuration. An especially-compact design is obtained in this configuration for the entire drive, that is, for the motor and the associated drive gear, so that the configuration as a whole may be integrated into the structure of the leg rest without design difficulties.

An especially simple design is obtained if the racks are mounted on the housing of the drive motor so as to be movable. The configuration may be configured so that the housing of the gear motor is cantilevered on the racks guided in it. The desired compact structure of the gear configuration as a whole is obtained, as well as the added advantage that an especially long displacement path may be achieved by means of the rack-and-pinion configuration, a path whose length is only slightly shorter than the combined length of the two racks.

In order to achieve the greatest possible length for the displacement path, that is, to employ racks of the greatest possible length, the configuration devised may be such that, when the foot rest configuration is in the retracted position, the ends of the racks are coupled to the structure of the leg rest and to the structure of the slide of the foot rest configuration at points at which the racks extend in approximation diagonally to the rectangular surface of the bottom elements of the leg rest and foot rest configuration and, accordingly, use which is optimal for the installed length racks is made of the entire structural space allotted for mounting of the gearing.

The invention will be described in greater detail below with the aid of exemplary embodiments illustrated in the drawings in which:

FIG. 1 shows a partly detached diagram of a side view only of the front edge area of the seat element of the exemplary embodiment of the aircraft passenger seat claimed for the invention, the seat cushion not being shown and the leg rest, with the foot rest configuration retracted into it, being only slightly elevated from the non-use position;

FIG. 2 shows a top view of the leg rest with the foot rest configuration retracted into it, drawn on a smaller scale, cushion carriers of leg rest and foot rest configuration being omitted, this permitting inspection of the box-like structures of leg rest and foot rest configuration; and

FIG. 3 a top view corresponding to FIG. 2, but with the foot rest configuration shown in the filly extended position.

FIG. 1 shows the front edge area of a seat element designated as a whole as 1, detached and without the seat cushion placed in position. At a pivot point 3 of the edge area the upper end of a carrier structure 7 for a pivotable leg rest 9 is shown by means of a joint bolt 5 in FIG. 1, as well as a foot rest configuration 11 which may be retracted into and extended from this leg rest 9. As is to be seen only in FIG. 1, a conventional hinged tread element 13, shown in the folded position in FIG. 1, is positioned at the (lower) front end of the foot rest configuration 11.

In FIG. 1 a cushion carrier of the leg rest 9, shown without cushion cover, is designated as 15. In addition, FIG. 1 shows the end area of a cushion carrier 17 of the foot rest configuration 11. Neither the cushion carrier 15 of the leg rest 9 nor the cushion carrier 17 of the foot rest configuration 11 is shown in FIGS. 2 and 3, so that it is possible to inspect the interior of the structures 7 and 21 of leg rest 9 and foot rest configuration 11, both of which are configured as flat boxes, the foot rest configuration 11 suitably telescoping into the carrier structure 7 of the leg rest 9, the side walls 19 of which form a displacement guide for the structure 21 of the leg rest 11.

As is to be seen in FIGS. 2 and 3, there is a pivot bearing 23 on the structure 7 of the leg rest 9 and a pivot bearing 25 on the structure 21 of the foot rest configuration 11. The end of a rack 27 is coupled to the pivot bearing 23 of the leg rest 9, while a similar rack 29 is coupled to the pivot bearing 25 of the foot rest configuration 11. The configuration of the racks 27 and 29 is such that they are movable in one common swiveling plane which extends in parallel with the primary plane of the bottom elements 31 and 33 of the structure 7 of the leg rest 9 and the structure 21 of the foot rest configuration 11. The racks 27 and 29 are contained in the housing 35 of an electric gear motor 37 so that the pinion of the latter on the output side (represented only by a circle 39 in FIGS. 2 and 3) is positioned between the two racks 27 and 29 and engages these two racks.

FIG. 2 shows a foot rest configuration 11 in the position in which it is fully retracted into the leg rest 9. As is to be seen, the coupling points of the racks 27 and 29 are displaced in relation to the primary longitudinal axis of leg rest 9 and foot rest configuration 11 so that the racks 27 and 29 extend in approximation diagonally to the rectangular surface defined by the bottom element 33 of the structure 21, with the result that the best possible use is made of the space available for accommodating the racks 27, 29, so that an advantageously longer displacement path is available because of the corresponding length of the racks 27, 29.

FIG. 3 shows a foot rest configuration 11 extended in approximation over three-quarters of its path. As is to be seen, approximately the combined length of the two racks 27, 29 is available for the length of the displacement path, so that a sufficiently great extension length is available despite the compactness provided in the retracted state. Comparison of FIG. 2 to FIG. 3 also indicates that the position of the unit consisting of gear motor 37 and gear housing 35 in relation to the structures 7 and 21 may be varied. This is due to the circumstance that the unit consisting of gear motor 37 and gear housing 35 is cantilevered on the racks 27 and 29.

The configuration described for the drive, in the form of a gear motor with pinion on the output side which engages two parallel racks 27, ensures both a great extension length despite the small structural length, which is limited by the distance between seat element and cabin floor, and also results in an especially compact configuration of the drive as a whole so that it can be installed without difficulty in the box-like structures 7 and 21 of leg rest 9 and foot rest configuration 11 below their cushion carriers 15, 17. 

1. An aircraft passenger seat having seat components such as backrest, seat element (1), and leg rest (9) which is coupled to the front edge area (3) of such seat component and which may be pivoted between a lowered non-use position and raised use position, and having a foot rest configuration (11) which is movable longitudinally on the leg rest (9) between a retracted position and an extended position to form an extension of the leg rest (9), and which is connected to a drive (35, 37) which may be switched between an inactive state of rest and an active state generating a displacement force for the foot rest configuration (11), characterized in that a reversible drive (35, 37) which may be switched to two active states is provided for optional generation of a displacement force for retraction or extension of the foot rest configuration (11).
 2. The aircraft passenger seat as claimed in claim 1, wherein the drive has an electric gear motor (35, 37) which permits reversal of the direction of rotation.
 3. The aircraft passenger seat as claimed in claim 2, wherein the gear motor (35, 37) has a pinion (39) on the output side which engages two racks (27, 29) positioned in parallel with each other one of which racks (27, 29) is coupled on the end side to the structure (7) of the leg rest (9) and the other of which racks (27, 29) is coupled on the end side to the foot rest configuration (11) which is movable in relation to this leg rest (9).
 4. The aircraft passenger seat as claimed in claim 3, wherein the racks (27, 29) are mounted on the housing (35) of the gear motor (35, 37) so that they may be displaced.
 5. The aircraft passenger seat as claimed in claim 4, wherein the gear motor (35, 37) with its housing (35) is mounted cantilevered on the racks (27, 29) mounted in such gear motor (35, 37).
 6. The aircraft passenger seat as claimed in claim 5, wherein the structure (7) of the leg rest (9) is configured as a flat box open at the top, the upper side of which is covered by a cushion carrier (15) of the leg rest (9) and on the side walls (19) of which extending from the cushion carrier (15) to the bottom element (31) of the box-like structure (7) there is provided a displacement guide for the foot rest configuration (11) retractable into the box-like structure (7) between cushion carrier (15) and bottom element (31).
 7. The aircraft passenger seat as claimed in claim 6, wherein the foot rest configuration (11) is designed as a hollowed box-shaped slide with a bottom element (33) which extends, when in the position with the leg rest (9) retracted into the structure (7), in close proximity to the bottom element (31) of the box-like structure of the leg rest (9), so that space remains between bottom element (33) of the foot rest configuration (11) and cushion carrier (15) of the leg rest (9) for the gear motor (35, 37) present therein.
 8. The aircraft passenger seat as claimed in claim 7, wherein the ends of the racks (27, 29) are mounted on the structure (7) of the leg rest (9) and on the structure (21) of the slide of the foot rest configuration (11) in relation to their primary longitudinal axis at coupling points (23, 25) displaced so that the racks (27, 29) extend in approximation diagonally to the rectangular surface of the bottom elements (31, 33) when the foot rest configuration (11) is in the retracted position. 